To attend the preview party for the $28.2-million Hollywood Hills compound flipped by actor-turned-developer Brad Blumenthal and his business partner Leo Hauser this summer you needed that valuable Tinseltown commodity: an invitation.

Turning onto a side street off Sunset Strip I left my car with the valet service and was greeted by about a half-dozen young men in suits with matching iPads bearing the name “The Agency.” One of these real estate agents, whose company is marketing the estate for sale, checked me off the guest list, and I moved to the driveway where a trio of Lamborghinis from a local dealer caught the eyes of passersby.

In the motor court, between the detached garage/gym and the main house, another Lamborghini was open to inspection. Small plates -- octopus, prosciutto and melon on a Popsicle stick, mini meatball sandwiches -- prepared by the chef of L.A.'s Ink restaurant were passed by a uniformed wait staff. Attendees lined up at the bar for libations.

The more senior real estate agents and brokers from the Agency were holding court in this central space. Billy Rose, Blair Chang and Mauricio Umansky shook hands as moneyed buyers, looky-loos and an assortment of beautiful people made their way into the main house or up the stairs to the guesthouse. Those who made the trek were rewarded with a drink station, an array of chocolates from a local chocolatier and intoxicating twilight views of the city.

By the time I was waiting at the valet again to make my way home, the cars of still-incoming guests were backed up more than a block. Valets ran to retrieve cars from nearby streets and make room for the next.

Standing beside me was a casually dressed man carrying a wrench. I had to ask.

“Do you always carry a wrench to open houses?”

As my car screeched down the hill, and I stepped into the street to retrieve it, he replied: “I am the plumber. We had a last-minute problem that needed fixing.”